Search

Die Stadt als ein lebendiges Hybrid aus Geb��uden, ��ffentlichem Raum und Menschen befindet sich im st��ndigen Wandel. ��u��ere Einfl��sse wie Technik, Mobilit��t oder auch Telekommunikation sind wesentliche Impulse dabei. In den letzten Jahrzehnten hat eine Welle der Technologie die Stadt ��berrollt, wodurch sich ihre Erscheinungsform bedeutsam ver��ndert hat. Zwischenmenschliche Kommunikation findet pl��tzlich nicht mehr in der ��ffentlichkeit, sondern vorwiegend hinter den eigenen vier W��nden statt. Die Nutzung ��ffentlicher Pl��tze und Stra��en hat sich vom Kommunikationsraum hin zum Mobilit��tsraum gewandelt. Die Folge ist eine permanente ��berschneidung von Orten und Nicht-Orten, von Lebensraum und Transitraum; und der Mensch befindet sich irgendwo dazwischen. St��dte werden allm��hlich zu austauschbaren Momenten und verschwinden gleichsam in ihrer Monotonie. Die Stadt wird zur Weltstadt und l��sst ihre Identit��t hinter sich. Um dieser Aporie zu entkommen und das Gleichgewicht in der Stadt wieder herzustellen, haben viele Stadtregierungen Gegeninitiativen gestartet. Das Gehen im st��dtischen Kontext r��ckt wieder in den Fokus, ��ffentlicher Raum wird erneut zum Kommunikationsraum und Stra��en werden zum Lebensraum. Die Stadt wird zur��ckerobert., The city as a living hybrid of buildings, public space and people is constantly changing. External influences such as technology, mobility or telecommunications are essential impulses. In recent decades, a wave of technology has overtaken the city and changed its appearance significantly. Suddenly, communication between people no longer takes place in public, but mainly behind one���s own four walls. The use of public squares and streets has changed from a communication space to a mobility space. The result is a permanent overlapping of places and nonplaces, of habitat and transit space; and the human being is somewhere in between. Cities are gradually becoming interchangeable moments, disappearing in their monotony. The city becomes a metropolis and leaves its identity behind. In order to escape this aporia and restore the balance in the city, many city governments have launched counter initiatives. Walking in an urban context comes back into focus again, public space becomes a space for communication and streets become a living space. The city is about to be recaptured.

After more than three decades of civil war in Northern Uganda waged by the rebel army the Lords’ Resistance Army (LRA) using large numbers of forced child soldiers within their ranks, the current research focuses on the psychological impact of war, displacement and rebel abductions on war-affected youths now placed in educational programs, and it focuses on understanding ways to foster psychological recovery and enhanced psychosocial support. In our first study, trained local screeners assessed the mental health status of male and female students in Northern Ugandan schools. The study aimed to disclose potential differences in mental health-related impairment in two groups, former child soldiers (n = 354) and other war-affected youth (n = 489), as well as to separate factors predicting mental suffering in learners. Almost all respondents had been displaced at least once in their life. Thirty percent of the girls and 50% of the boys in the study reported past abduction history. Trauma exposure was notably higher in the group of abductees. The post-traumatic stress disorder (PTSD) rate in former child soldiers, 32%, was remarkably higher than that in non-abductees (12%). A path-analytic model for developing PTSD and potential depression revealed both previous trauma exposure and duration of abduction to have significant influences on trauma-related mental suffering. Findings suggest that in Northern Ugandan schools, trauma spectrum disorders are common among war-affected learners, and we have therefore recommended the school context to be further utilized and researched to provide mental health support for war-affected youth. In our second study, trained local screeners assessed the mental health status of male and female students in vocational training centers in Northern Uganda. The study aimed to explore the applicability and measurability of the newly emerging concepts of openness to reconciliation and revenge in the context of Northern Uganda and to understand their interplay with measures of PTSD, depression, aggression and stigmatization. In the study sample of war-affected learners (N = 406), we found that the two sub-scales “openness to reconciliation” and “revenge” were applicable to the majority of respondents (n = 325). Factor analysis and internal consistency supported this finding. Correlations revealed strong associations between the measures of psychopathology and maladjustment across genders. Respondents with a PTSD diagnosis (n = 94) had lower scores in openness to reconciliation and higher scores in vengeful feelings, aggression, and stigmatization. The results underline that mental health status, particularly PTSD diagnosis, among Ugandan youths is strongly interrelated with measures of openness to reconciliation, revenge, aggression and stigmatization. While we acknowledge that more research is needed with regards to the nature and direction of the found associations among the variables, it appears that suffering from PTSD diagnosis is a potential obstacle for reconciliation and peace-building attempts. In our third study, we tested the feasibility and efficacy of delivering group-based trauma and reconciliation education (n = 135), group-based conflict resolution and social competence training (n = 136), and individual teacher counseling (n = 135) carried out by local lay counselors in a randomized controlled research design. We assessed the intervention groups prior to the start of the interventions, at five months after the interventions, and at nine months after the interventions, with very low drop-out rates. In intention-to-treat (I-T-T) and treatment-completer (T-C) analysis of variance, we obtained the main effects for time for all three treatment conditions on all dependent variables, but no meaningful interaction effects between treatment conditions and times. We obtained medium effect sizes (Cohen’s d) for PTSD as an outcome measure, while we found high effect sizes for outcomes of depression, as well as for all post-war reconciliation measures. The study provides preliminary support for the feasibility and effectiveness of all three culturally and contextually adapted classroom-based interventions when implemented with former child soldiers and other war-affected learners in Northern Ugandan schools. The study further provides evidence that in randomized controlled trial (RCT) research designs, tailored mental health and psychosocial support (MHPSS) programs not only have beneficial effects on strained psychological health of war-affected learners, but also on societal post-war reconciliation and peace building after crisis. We discuss our findings’ implications for future research needs and the further development of group-based psychosocial interventions in LRA-affected areas, for the reintegration of former child soldiers, such as in (child) disarmament, demobilization and reintegration (DDR) programs, and for MHPSS programs using curriculum-based intervention (CBI) in educational settings. published

The subject of this thesis is the development of a chemical bath deposition (CBD) route for magnesium doped zinc oxide (ZnMgO) - a wide band, n-type semiconductor material. ZnMgO is relevant for a wide range of applications, among others for optical coatings, optoelectronic devices (such as touch screens and light emitting diodes) and thin film photovoltaics (TFPV). In the last case, where this thesis focuses, ZnMgO is mainly investigated as buffer layer, combined with chalcogenide (Cu-In-Ga-S(Se) and CdTe), kesterite (Cu-Zn-Sn-S(Se)) or oxide (e.g. Cu2O) absorbers [1], [2]. The motivation to use ZnMgO does not only arise from its appropriate and tunable electronic properties (such as the band-gap width), but also from the fact that it consists exclusively of earth-abundant and non-toxic elements. To achieve high power conversion efficiency in a solar cell, the band-offset between buffer layer and absorber is a critical parameter. The commonly used buffer layer material that matches absorbers of well-established thin film technologies, namely cadmium telluride (CdTe) and Cu-In-(Ga)-S(Se) (CIGS), is the toxic cadmium sulfide (CdS). The replacement of this enviromentally harmful material with alternatives that possess similar or better properties, is of outmost importance, as it will render TFPV more attractive for large scale implementation. ZnMgO has the benefit of a tunable band gap (3.37 - 4 eV) [3] depending on the Mg content in the ZnO lattice, which can be used to optimize band offsets with various absorber materials. So far, ZnMgO films were mainly deposited by vacuum techniques. In order to lower the production costs, simple methods without expensive equipment, like chemical bath deposition (CBD), are desired. The available literature on solution-processed Zn- MgO films is very limited. This thesis provides a fundamental investigation on the CBD of ZnMgO films. The solution chemistry was theoretically examined via speciation modelling. Experimentally it was found that deposition is only possible in a narrow pH window, due to the pH-dependent supersaturation of Zn(OH)2 as a precursor for ZnO. The highest amount of magnesium incorporated into the ZnO lattice was 2.1%, quantified via inductively coupled plasma - optical emission spectroscopy measurements, suggesting that further incorporation is not possible, due to the thermodynamic solubility limit of 4 mol% under equilibrium conditions [4]. Although the achieved band-gap variation of 3.43-3.55 eV for the deposited ZnMgO films is moderate, the smooth, orientated and highly transparent (>80%) films, have implementation potential as buffer layers in solar cells . It was further shown by X-ray diffraction, that the amount of certain Mg species in the solution defines the ZnO film morphology. The cause of this, is most likely faceselective adsorption of the bulky [MgCit]-, as well as Mg2+ and Mg(OH)+ species onto 11 specific ZnO faces. Film morphologies with dominant (100), (101) or (002) ZnO crystal faces were observed depending on the solution composition. Further, a correlation between Mg incorporation and the growth mechanism was proposed. The precise control of the surface morphology allows to optimize the absorber/buffer interface and therefore the conversion efficiency. The ZnMgO films were finally implemented into a Cu2O/ZnMgO type of solar cell, showing rectification characteristics and leading to measurable photovoltaic performance. 12

Background: Trained local screeners assessed the mental-health status of male and female students in Northern Ugandan schools. The study aimed to disclose potential differences in mental health-related impairment in two groups, former child soldiers (n = 354) and other war-affected youth (n = 489), as well as to separate factors predicting mental suffering in learners.Methods: Participants were randomly selected. We used the Post-Traumatic Diagnostic Scale to assess symptoms of post-traumatic stress disorder (PTSD) and for potential depression the respective section of the Hopkins Symptom Checklist with a locally validated cut-off.Results: Almost all respondents had been displaced at least once in their life. 30% of girls and 50% of the boys in the study reported past abduction history. Trauma exposure was notably higher in the group of abductees. In former child soldiers, a PTSD rate of 32% was remarkably higher than that for non-abductees (12%). Especially in girls rates of potential depression were double those in the group of former abductees (17%) than in the group of non-abductees (8%). In all groups, trauma exposure increased the risk of developing PTSD. A path-analytic model for developing PTSD and potential depression revealed both previous trauma exposure as well as duration of abduction to have significant influences on trauma-related mental suffering. Findings also suggest that in Northern Ugandan schools trauma spectrum disorders are common among war-affected learners.Conclusions: Therefore, it is suggested the school context should be used to provide mental-health support structures within the education system for war-affected youth at likely risk of developing war-related mental distress.

Die vorliegende Diplomarbeit stellt eine heilpädagogische Auseinandersetzung zum Thema „ADHS – Aufmerksamkeitsdefizits- und Hyperaktivitätsstörung“ dar und befasst sich mit der medienpädagogischen Fragestellung: „Wie nutzen Kinder mit ADHS-Diagnose das Medium Fernsehen“. Die Subfragen umfassen Fragen zum Stellenwert von Fernsehen für Kinder mit diagnostizierter ADHS und dem Zusammenhang zwischen dem Fernsehkonsum und der Verhaltensproblematik ADHS. Ausgehend von der Hypothese, dass Kinder mit einer ADHS sich in ihrem Nutzungsverhalten des Mediums "Fernsehen" von Kindern ohne ADHS-Diagnose unterscheiden, wurden jeweils zwei Kinder mit ADHS-Diagnose und zwei Kinder ohne diagnostizierter ADHS zwischen neun und elf Jahren mittels qualitativem Leitfadeninterview zu ihrem Fernsehverhalten befragt. Anschließend wurden die Ergebnisse der Transkription anhand der Inhaltsanalyse nach Mayring ausgewertet und miteinander verglichen. Die Grundlage der wissenschaftlichen Arbeit bildet die heilpädagogische und medienpädagogische Positionierung sowie eine konkrete theoretische Auseinandersetzung mit der Verhaltensproblematik ADHS. Fazit dieser Arbeit ist, dass Kinder mit ADHS-Diagnose nicht anders als Kinder ohne diagnostizierter ADHS auf den medialen Einfluss des Fernsehens reagieren. Fernsehen spielt im Leben beider befragten Gruppen eine große Rolle, wobei der Comedyfaktor und das Interesse an den Lieblingssendungen als Motive angegeben werden. Alle befragten Kinder gaben an ein gutes Gefühl beim Fernsehen zu empfinden. Ein bedeutsamer Unterschied besteht hinsichtlich der emotionalen Wahrnehmung während des Fernsehens: Kinder mit ADHS-Diagnose sind nie aufgeregt wenn sie fernsehen, auch nicht wenn spannende Inhalte vermittelt werden. Weiter messen Kinder mit ADHS-Diagnose dem Fernsehen laut den Ergebnissen dieser Studie keinen speziellen Stellenwert zu. Negative Verbindungen zwischen dem Fernsehen und der Verhaltensproblematik konnten nicht aufgezeigt werden.

Hochwasserrückhaltebecken (HRB) als Teile von HRB-Systemen werden derzeit üblicherweise eigenständig betrachtet und entsprechend gesteuert. Meist wird dabei mit einer festen Schieberstellung bzw. mit einer konstanten Regelabgabe gesteuert. Diese Steuerung führt bei extremen Hochwasserereignissen und Abflüssen aus Zwischeneinzugsgebieten nicht zur bestmöglichen Reduktion von Schäden. In der vorliegenden Forschungsarbeit wird ein Verfahren zur Optimierung der Steuerung von HRB-Systemen bei extremen Hochwasserereignissen und Abflüssen aus Zwischeneinzugsgebieten vorgestellt. Dabei wird die räumliche Verteilung der Schadensstellen und ihre Beeinflussung durch Teilsysteme berücksichtigt. Die Optimierung erfolgt simulationsgestützt durch ein N-A-Modell. Die Optimierung dient der Minimierung von Schäden durch Hochwasser im Einzugsgebiet. Die Schadenshöhe wird über die Abflüsse an potentiellen Schadensstellen parametrisiert. Das Optimierungsmodell liefert eine optimierte Steuerung für ein betrachtetes Hochwasserereignis. Dieses kann mehrgipflige Wellen umfassen und dauert bis zum vollständigen Abwirtschaften des HRB-Systems an. Es wird angenommen, dass bei einer länger dauernden geringen Überschreitung der Leistungsfähigkeit weniger Schäden entstehen als bei einer kurzen extremen Überschreitung. Bei der Optimierung werden folgende Informationen ausgewertet: (1) Der räumlich und zeitlich variable Systemzustand des Einzugsgebiets, (2) das Zusammenwirken der HRB im HRB-System und (3) die Niederschlags- bzw. Abflussvorhersage. Die beiden ersten Informationgruppen werden über ein Regelsystem erfasst. Die Regeln dieses Regelsystems dienen bei der Optimierung zur Auswertung der Niederschlagsvorhersage als Nebenbedingungen. Für die Entwicklung des Regelsystems wurden die HRB mittels dreier Kriterien klassifiziert: (1) Zugehörigkeit zu Teilsystemen, (2) Ebene der HRB innerhalb des HRB-Systems und (3) Konsequenzen des Anspringens der Hochwasserentlastungen der HRB. Diese drei Kriterien ermöglichen eine Dekomposition des HRB-Systems. Jedem HRB werden dabei Schadensstellen im Unterlauf zugeordnet, die von ihm unmittelbar und in relevantem Ausmaß beeinflusst werden. Die Niederschlagsvorhersage wird über eine iterative Anpassung der zeitlich variablen Beckenabgabe und eines maximalen Abflusses an den Schadensstellen berücksichtigt. Teilsysteme werden in der Optimierung des HRB-Systems zunächst aggregiert betrachtet. Das Optimierungsverfahren kann als heuristischer Dekompositions-Aggregationsansatz mit iterativer Teilsystemoptimierung klassifiziert werden. Durch sukzessives Verschieben des Optimierungshorizonts können bei einer Echtzeitberechnung jeweils aktuelle gemessene Systemzustände und aktualisierte Vorhersagen berücksichtigt werden. Ferner kann durch den gleitenden Optimierungshorizont frühzeitig auf Folgewellen mehrgipfliger Ereignisse reagiert werden. Das Optimierungsverfahren wurde am Beispiel des HRB-Systems des Wasserverbands Obere Jagst mit 15 HRB und einem Einzugsgebiet von ca. 400 km² entwickelt. Durch eine Trennung von Programmcode und Eingangsdaten kann es für jedes vergleichbare HRB-System angewandt werden. Systemänderungen können untersucht werden, ohne dass der Programmcode geändert werden muss. Es bestehen keine prinzipiellen Einschränkungen hinsichtlich der Anzahl der zu berücksichtigenden HRB. Das Optimierungsverfahren wurde am Beispiel eines extremen Hochwasserereignisses im untersuchten Einzugsgebiet entwickelt. Eine Validierung erfolgte anhand eines weiteren extremen Hochwasserereignisses. Das Optimierungsverfahren zeigte bei den beiden untersuchten Ereignissen gute und plausible Ergebnisse. Um die Sensitivität des Modells gegenüber verschiedenen Eingangsdaten und verschiedenen Nebenbedingungen der Optimierung festzustellen, wurde eine Sensitivitätsanalyse durchgeführt. Auf ihrer Basis wurden Vorschläge zur Generierung von Szenarien erarbeitet, die zur Berücksichtigung der Unsicherheit der Eingangsdaten berechnet werden sollen. Weiterhin wurden aufbauend auf Szenarienuntersuchungen Diagramme entwickelt, die im Hochwasserfall bei einem Ausfall der Datenübertragungssysteme und den damit verbundenen Einschränkungen von Echtzeitberechnungen eine verbesserte Steuerung im Vergleich zur Regelsteuerung ermöglichen sollen. Hierfür wurden 540 Szenarien mit synthetischen Eingangsdaten berechnet und ausgewertet. Dabei wurden die Anfangswasserstände des HRB-Systems, die Niederschlagsdauer, die Niederschlagshöhen, deren zeitliche Verteilung und die Vorbodenfeuchte variiert. Auf Basis der entwickelten Diagramme kann die Gefährdung von Schadensstellen und HRB eingeschätzt werden. Abschließend wurden die gewonnenen Erkenntnisse zur Steuerung von HRB-Systemen im Hinblick auf den Entwurf von HRB-Systemen ausgewertet. Es wurden Vorschläge zur Bemessung von HRB als Bestandteile verschiedener Teilsysteme erarbeitet. Diese können als Hilfsmittel bei dem Entwurf von HRB-Systemen dienen., At present, flood-control reservoirs of multi-reservoir systems are usually considered as independent and accordingly operated as such. Operation is mostly performed with fixed gate positions and a constant standard release. However, this kind of operation does not necessarily lead to the best possible reduction of damages in cases of extreme floods and discharges from areas between the flood retention basin and the place of damage. This research work presents a procedure to optimize the operation of multi-reservoir systems in case of extreme floods and discharges from subcatchments between reservoirs and places of damage. Thereby the influence of subsystems and the spatial distribution of the places of damage are taken into consideration. The optimization is carried out simulation-supported by a rainfall-runoff model. The purpose of the optimization is to minimize flood damages in the catchment area. The amount of damages is parameterized by the discharges at potential places of damage. The optimization model supplies an optimized operation for an examined flood event. This may include flood events with multiple flood crests and lasts until all reservoirs of the multi-reservoir system are emptied. It is assumed that a longer, less extreme exceeding of the capability is causing less damages than a shorter but more extreme exceeding. The following information is analysed for the optimization: (1) the spatially and temporally variable system status of the catchment area, (2) the interaction of the basins in the multi-reservoir system and (3) the precipitation and discharge forecast. The first two groups of information are integrated into the optimization procedure using a rule system. The rules serve as constraints for the implementation of the precipitation forecast. For the development of the rule system, the basins were classified using three criteria: (1) membership in a subsystem, (2) level of the flood-control reservoir within the multi-reservoir system and (3) consequences of spilling of the basins. These three criteria enable a decomposition of the multi-reservoir system. Places of damage lying downstream which are directly and to a relevant extent influenced by a basin are thereby related to this basin. Precipitation forecast is taken into consideration by iteratively adjusting the temporal variable basin discharge and a maximum discharge at places of damage. Subsystems are initially considered as aggregated for the optimization of the multi-reservoir system. The optimization procedure can be classified as heuristic decomposition-aggregation approach with iterative subsystem optimization. Having a real-time computation, online measured system states and updated forecasts can be considered by successively sliding the optimization horizon. In addition reactions to succeeding waves of flood events with multiple crests are possible at an early stage due to the sliding optimization horizon. The optimization procedure is exemplarily accomplished as a case study of the multi-reservoir system of the „Wasserverband Obere Jagst“ which consists of 15 flood detention basins and has a catchment area of about 400 km². By separating source code and input data it is applicable to comparable multi-reservoir systems. Changes to the system can be examined without modifying the source code. There are no principle restrictions concerning the number of examined reservoirs. The optimization procedure has been developed using the data of an extreme flood event in the examined catchment area. Validation was accomplished using the data of another extreme flood event. The optimization procedure showed good and plausible results for both investigated events. In order to assess the models sensitivity to different input data and optimization constraints, a sensitivity analysis was performed. Based on this analysis propositions for the generation of scenarios were developed which are to be computed in order to consider the uncertainty of the input data. Additionally, based on scenario computations diagrams were developed, which in case of a breakdown of the data transmission systems during a flood event and the constrictions of real-time computation associated therewith will permit an improved operation compared to standard operation. For this purpose, 540 scenarios with synthetic input data were calculated and evaluated. The initial water levels of the multi-reservoir system, the duration and the amount of precipitation, the temporal distribution and the antecedent soil moisture were varied thereby. Finally, the obtained results on operating multi-reservoir systems were analysed with regard to designing multi-reservoir systems. Propositions for the dimensioning of flood-control reservoirs being part of different subsystems were worked out. These may serve as an aid when designing multi-reservoir systems.